Cheating hubby Arnold Schwarzenegger was so fond of the son he had with his housekeeper, he jetted him around on family vacations with his unsuspecting wife and kids and played the role of godfather to the boy’s older brother, The Post has learned.

Word of the bizarre, tangled, relationship came as another women, an unknown actress, claimed to have had an affair with the horny muscleman and immediately hired a celebrity lawyer.

As his personal life imploded, the “Terminator” star put his promised film comeback on hold.

“Schwarzenegger is focusing on personal matters and is not willing to commit to any production schedules or timelines,” his rep said.

Schwarzenegger doted on his out-of-wedlock son with Mildred “Patty” Baena.

He’d dole out wads of holiday cash and presents to both his son and his godson, Roger — from PlayStations and other electronics to an annual pass to Universal Studios — making the kids the envy of their neighborhood.

“We thought it was strange that he was so lavish with them,” Baena’s former daughter-in-law, Nora Vela, told The Post,

“Roger and [Patty’s son with Arnold] would get all of these gifts and then they would go on vacations with Arnold, Maria and their kids,” Vela said.

“It just seemed strange that they were so close.”

“[Patty] kept saying the boy was not Arnold’s,” Vela recalled.

“We were constantly asking, but she would always say, ‘No! No!’ ”

Meanwhile bit-part actress Gigi Goyette Jeffers hired Limelight-loving lawyer Gloria Allred and proclaimed she began bedding the former Mr. Universe when she was only 16.

Jeffers, 52, whose claim to fame was a kid’s role in “Little House on the Prairie,” said she was wooed by Schwarzenegger while riding a horse to a Malibu restaurant in 1975.

He complimented her on her derriere, and the two soon began sleeping together, she told The National Enquirer several years ago, adding they had steamy annual hookups for years.

In 2005, press reports said she was paid $20,000 to keep mum about their trysts during his run for governor.

Housekeeper Baena remained in hiding yesterday with Schwarzenegger’s son and her current partner, Alejandro Aguiar.

Vela — divorced from Baena’s eldest son, John, 32 — said Schwarzenegger kept the love, and the money, in the family.

Roger Baena, now in his early 20s, was a toddler when Schwarzenegger was named his godfather, Vela recalled.

“He opened Roger’s first savings account with $2,000 for the occasion,” she said.

“It was a big deal.”

As the boy grew — and after Baena gave birth to Schwarzenegger’s son in 1997 — the relationship with both boys flourished, according to Vela.

“When Roger turned 18, Arnold got him a job as a makeup artist, working with one of the big studios,” she said.

Roger did not respond to phone messages.

Adding insult to injury, Baena and Schwarzenegger would have sex in the same bed he shared with Shriver — with the housekeeper sometimes slipping between the sheets after Maria left the house, TMZ said.

Baena also played dress-up in Shriver’s clothes and paraded around in her jewelry, according to the Web site.

The Sperminator’s sordid scandal finally came to light after Shriver — suspecting something was up — asked Baena flat out if Schwarzenegger was her son’s dad.

The housekeeper broke down and admitted the truth, according to RadarOnline.com.